Zeitschrift für Rheumatologie

, Volume 65, Issue 5, pp 400–406

Neue pathophysiologische Stoffwechselwege in der Osteoporose

Zukünftige innovative Therapieansätze?
Leitthema
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Zusammenfassung

Die Osteoporose ist durch geringe Knochendichte und mikroarchitektonische Veränderungen gekennzeichnet. Dies führt zur verminderten knöchernen Stabilität und somit zur erhöhten Anfälligkeit für Frakturen. Der Knochenumbau beim gesunden Menschen findet durch ein ausgeglichenes Verhältnis von Knochenresorption zu Knochenaufbau statt. Auf zellulärem Niveau wird dieser Prozess über die Osteoklasten- und Osteoblastenaktivität reguliert. Bei Verlust der Knochendichte besteht ein Ungleichgewicht auf Seiten der Aktivierung von Osteoklasten. Die Osteoklastenaktivierung ist daher das Ziel vieler Untersuchungen. So werden z. B. die Einflüsse von Östrogen, Wnt und dem RANK/RANKL/OPG-System untersucht. Letztere sind aktiv an der Reifung und Funktion von Osteoklasten beteiligt und scheinen eine zentrale Rolle bezüglich der meisten pathophysiologischen Mechanismen in der Osteoporose einzunehmen.

Schlüsselwörter

RANK RANKL OPG Osteoporose Osteoklastogenese 

New pathophysological relevant metabolic pathways in osteoporosis

Future innovative therapies?

Abstract

Osteoporosis is characterized by low bone mass and by changes in the microarchitecture of the bone. This leads to reduced bone stability and altered suscebtibility to fractures. Bone remodelling in healthy persons is characterized by a balance between bone resorption and bone formation. At the cellular level, bone remodelling is regulated by osteoclast and osteoblast activity. During bone loss, there is an imbalance, osteoclast activity being more pronounced. Therefore, the influende of estrogens, Wnt and the RANK/RANKL/OPG system on osteoclastogenesis and osteoclast activity has been investigated. The RANK/RANKL/OPG-System is actively involved in the differentiation and function of osteoclasts and seems to play a central part in most pathophysiological mechanisms that are active in osteoporosis.

Keywords

RANK RANKL OPG Osteoporosis Osteoclastogenesis 

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Copyright information

© Springer Medizin Verlag 2006

Authors and Affiliations

  1. 1.Abteilung für Innere Medizin mit Schwerpunkt Rheumatologie der Justus-Liebig-Universität Giessen, Abteilung für Rheumatologie und Klinische ImmunologieKerckhoff-KlinikBad Nauheim

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